The goals of this project are (1) to establish and define a cell culture transformation system for identification of individuals predisposed to cancer genetically or by virtue of exposure to environmental carcinogens; (2) to develop human cell transformation systems, with particular emphasis on epithelial cells, in order to study host factors regulating cell transformation and the mechanisms of carcinogenesis by chemicals, viruses, hormones and x-irradiation; (3) to identify and rescue human and/or primate sarcoma (src) information; and (4) to develop and test measures to prevent and/or control cell transformation and the neoplastic event for eventual application in primates, including humans.